Study to determine the likely accuracy of pH testing to confirm nasogastric tube placement

Objective To establish the likely accuracy of pH testing to identify gastric aspirates at different pH cut-offs to confirm nasogastric tube placement.Methods This prospective observational study included a convenience sample of adult patients who had two (one fresh and one frozen) gastric and oesophageal samples taken during gastroscopy or two bronchial and saliva samples taken during bronchoscopy. The degree of observer agreement for the pH of fresh and frozen samples was indicted by kappa (k) statistics. The sensitivities and specificities at pH ≤5.5 and the area under the receiver operating characteristics (ROC) curve at different pH cut-offs were calculated to identify gastric and non-gastric aspirates.Results Ninety-seven patients had a gastroscopy, 106 a bronchoscopy. There was complete agreement between observers in 57/92 (62%) of the paired fresh and frozen gastric samples (k=0.496, 95% CI 0.364 to 0.627). The sensitivity of a pH ≤5.5 to correctly identify gastric samples was 68% (95% CI 57 to 77) and the specificity was 79% (95% CI 74 to 84). The overall accuracy to correctly classify samples was between 76% and 77%, regardless of whether patients were taking antacids or not. The area under the ROC curve at different pH cut-offs was 0.74.Conclusion The diagnostic accuracy of pH ≤5.5 to differentiate gastric from non-gastric samples was low, regardless of whether patients were taking antacids or not. Due to the limited accuracy of the pH sticks and the operators’ ability to differentiate colorimetric results, there is an urgent need to identify more accurate and safer methods to confirm correct placement of nasogastric tubes

Diagnostic accuracy of a pH stick, modified to detect gastric lipase, to confirm the correct placement of nasogastric tubes

Objective The correct placement of a nasogastric feeding tube is usually confirmed by establishing that an aspirate is acidic using a pH stick. However, antacid medication and achlorhydria can cause false negative pH tests that may delay feeding and increase resource use. The purpose of this study was to evaluate a modified pH stick designed to detect gastric lipase and therefore reduce false negativetests.Methods In this prospective observational study, a convenience sample of adult patients who had either gastric and oesophageal samples taken during routine diagnostic gastroscopy (n=97) or bronchial and saliva samples taken during a bronchoscopy (n=106). The samples were tested by blinded observers using the modified and standard pH sticks. The sensitivities and specificities of the two pH sticks in identifying gastric and non-gastric aspirates were compared using the pH cut-off ≤5.5.Results The sensitivities of a pH≤5.5 to correctly identify gastric samples were 66% (95% CI 56 to 75) and 68% (95% CI 57 to 77) for the modified and the standard pH, respectively. The specificities were 81% (95% CI 76 to 85) and 79% (95% CI 74 to 84). There were no significant differences in the distribution of the discordant resultsbetween the paired gastric and non-gastric samples for both the modified and standard pH sticks at pH≤5.5 (both McNemar’s tests, p≥0.05).Conclusions There were no significant differences between the paired modified and standard pH tests for the gastric samples. Due to the limited accuracy of pH sticks, further research is required to identify accurate and cost-effective bedside methods to confirm the correct placement of nasogastric tubes

Development and evaluation of a nurse-led, tailored stroke self-management intervention.

Community nurses are well placed to promote and support stroke survivors to engage in self-management. The aim of this study was to develop a stroke self-management intervention that could be tailored towards stroke survivors’ self-management needs, goals and levels of activation, in the first year post-stroke.MethodsMixed method study, designed in accordance with the British Medical Research Council’s (MRC) guidance for the development and evaluation of complex interventions. The intervention was developed and evaluated in two phases. The intervention was underpinned by the theoretical concept of patient activation and was developed based on a review of published research on stroke self-management interventions and qualitative interviews and focus groups (phase 1). It was evaluated using qualitative interviews and focus groups with stroke survivors and stroke nurses (phase 2). Participants comprised 26 stroke survivors, between 3 and 12 months post stroke and 16 stroke nurses, from across three NHS Boards in Scotland.ResultsThe intervention consisted of a tailored self-management action plan, incorporating an individualised assessment of stroke survivor’s readiness to self-manage (using the Patient Activation Measure), goal setting and motivational interviewing. Evaluation showed that many of the individual components of the intervention were perceived as feasible and acceptable to both stroke survivors and stroke nurses.ConclusionsTo our knowledge, this is the first UK study to explore the use of patient activation as a theoretical underpinning in stroke self-management research and to involve stroke survivors and stroke nurses in the design and development of a tailored, person-centred stroke self-management support intervention. The study findings provide the first step in understanding how to effectively develop and deliver stroke self-management support interventions to stroke survivors living at home in the first year following stroke. Further work is needed to develop and refine the intervention and identify how to effectively embed it into nurses’ routine clinical practice

Clinical symptoms, signs and tests for identification of impending and current water-loss dehydration in older people (Review)

BackgroundThere is evidence that water-loss dehydration is common in older people and associated with many causes of morbidity and mortality.However, it is unclear what clinical symptoms, signs and tests may be used to identify early dehydration in older people, so that support can be mobilised to improve hydration before health and well-being are compromised.ObjectivesTo determine the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs and tests to be used as screeningtests for detecting water-loss dehydration in older people by systematically reviewing studies that have measured a reference standard and at least one index test in people aged 65 years and over. Water-loss dehydration was defined primarily as including everyone with either impending or current water-loss dehydration (including all those with serum osmolality ≥ 295 mOsm/kg as being dehydrated).Search methodsStructured search strategies were developed for MEDLINE (OvidSP), EMBASE (OvidSP), CINAHL, LILACS, DARE and HTAdatabases (The Cochrane Library), and the International Clinical Trials Registry Platform (ICTRP). Reference lists of included studiesand identified relevant reviews were checked. Authors of included studies were contacted for details of further studies.Selection criteriaTitles and abstracts were scanned and all potentially relevant studies obtained in full text. Inclusion of full text studies was assessed independently in duplicate, and disagreements resolved by a third author. We wrote to authors of all studies that appeared to have collected data on at least one reference standard and at least one index test, and in at least 10 people aged ≥ 65 years, even where no comparative analysis has been published, requesting original dataset so we could create 2 x 2 tables.Data collection and analysis.Diagnostic accuracy of each test was assessed against the best available reference standard for water-loss dehydration (serum or plasma osmolality cut-off≥295mOsm/kg, serumosmolarity or weight change) within each study. For each index test study data were presented in forest plots of sensitivity and specificity. The primary target condition was water-loss dehydration (including either impending or current water-loss dehydration). Secondary target conditions were intended as current (> 300 mOsm/kg) and impending (295 to 300 mOsm/kg) water-loss dehydration, but restricted to current dehydration in the final review.We conducted bivariate random-effects meta-analyses (Stata/IC, StataCorp) for index tests where there were at least four studies and study datasets could be pooled to construct sensitivity and specificity summary estimates. We assigned the same approach for index tests with continuous outcome data for each of three pre-specified cut-off points investigated.Pre-set minimum sensitivity of a useful test was 60%, minimum specificity 75%. As pre-specifying three cut-offs for each continuoustest may have led to missing a cut-off with useful sensitivity and specificity, we conducted post-hoc exploratory analyses to createreceiver operating characteristic (ROC) curves where there appeared some possibility of a useful cut-off missed by the original three.These analyses enabled assessment of which tests may be worth assessing in further research. A further exploratory analysis assessed the value of combining the best two index tests where each had some individual predictive ability.Main resultsThere were few published studies of the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs or tests tobe used as screening tests for detecting water-loss dehydration in older people. Therefore, to complete this review we sought, analysed and included raw datasets that included a reference standard and an index test in people aged ≥ 65 years.We included three studies with published diagnostic accuracy data and a further 21 studies provided datasets that we analysed. Weassessed 67 tests (at three cut-offs for each continuous outcome) for diagnostic accuracy of water-loss dehydration (primary targetcondition) and of current dehydration (secondary target condition).Only three tests showed any ability to diagnose water-loss dehydration (including both impending and current water-loss dehydration) as stand-alone tests: expressing fatigue (sensitivity 0.71 (95% CI 0.29 to 0.96), specificity 0.75 (95% CI 0.63 to 0.85), in one study with 71 participants, but two additional studies had lower sensitivity); missing drinks between meals (sensitivity 1.00 (95% CI 0.59 to 1.00), specificity 0.77 (95% CI 0.64 to 0.86), in one study with 71 participants) and BIA resistance at 50 kHz (sensitivities 1.00 (95% CI 0.48 to 1.00) and 0.71 (95% CI 0.44 to 0.90) and specificities of 1.00 (95% CI 0.69 to 1.00) and 0.80 (95% CI 0.28 to 0.99) in 15 and 22 people respectively for two studies, but with sensitivities of 0.54 (95% CI 0.25 to 0.81) and 0.69 (95% CI 0.56 to 0.79) and specificities of 0.50 (95% CI 0.16 to 0.84) and 0.19 (95% CI 0.17 to 0.21) in 21 and 1947 people respectively in two other studies). In post-hoc ROC plots drinks intake, urine osmolality and axillial moisture also showed limited diagnostic accuracy. No test was consistently useful in more than one study.Combining two tests so that an individual both missed some drinks between meals and expressed fatigue was sensitive at 0.71 (95%CI 0.29 to 0.96) and specific at 0.92 (95% CI 0.83 to 0.97).There was sufficient evidence to suggest that several stand-alone tests often used to assess dehydration in older people (including fluid intake, urine specific gravity, urine colour, urine volume, heart rate, dry mouth, feeling thirsty and BIA assessment of intracellular water or extracellular water) are not useful, and should not be relied on individually as ways of assessing presence or absence of dehydration in older people.No tests were found consistently useful in diagnosing current water-loss dehydration.Authors’ conclusionsThere is limited evidence of the diagnostic utility of any individual clinical symptom, sign or test or combination of tests to indicatewater-loss dehydration in older people. Individual tests should not be used in this population to indicate dehydration; they miss a highproportion of people with dehydration, and wrongly label those who are adequately hydrated.Promising tests identified by this review need to be further assessed, as do new methods in development. Combining several tests may improve diagnostic accuracy

Conclusion to the stroke series.

ALL ARTICLES PUBLISHED as part of the stroke series highlighted that caring for stroke patients is motivating, stimulating and skilful. Throughout the series the authors have used current research plus their experiences of clinical practice to discuss the many physical, psychological and social problems that patients and carers experience following stroke. The articles highlighted that nurses can intervene to prevent complications, such as malnutrition, dehydration, incontinence, shoulder pain and poor oral hygiene, and provide effective strategies to care for stroke patients with communication impairment

Malnutrition and dehydration after stroke

By identifying malnutrition and dehydration in patients who have had a stroke, nurses can intervene to prevent significant complications developing and so improve patient outcomes. Poor intake of fluid and food may result from difficulties in swallowing, as well as other physical and functional problems that occur as a result of a stroke. The aim of this article is to encourage nurses to identify the frequency and causes of malnutrition and dehydration, to consider the complications this can cause and to be aware of optimum feeding strategies for stroke patient

Patient positioning and its effect on brain oxygenation.

Stroke remains the third most common cause of death and the leading cause of major disability in the developed world. Recent evidence from randomised controlled trials (RCTs) suggests that some pharmacological treatments, such as aspirin (Chinese Acute Stroke Trial Collaborative Group, 1997; International Stroke Trial Collaborative Group, 1997) and thrombolytic ('clot-busting') drugs (Wardlaw et al, 1999), may be beneficial for particular subgroups of stroke patients. However, the benefits of pharmacological treatments are rather modest when compared to 'organised care' on a stroke unit (Stroke Unit Trialists' Collaboration, 1998)

Introduction to the stroke series

THIS ARTICLE is an introduction to a series of articles outlining the priorities of stroke care. The aim of these articles is to raise nurses’ awareness of caring for stroke patients with complex problems in a range of care environments, to enhance knowledge and improve understanding of stroke. The focus is on evidence-based practice and the application of stroke competencies and national guidelines to help readers in their future clinical practice. Stroke is a clinical syndrome characterised by the rapid onset of focal cerebral deficits of vascular origin that last more than 24 hours or result in death. Transient ischaemic attack (TIA) refers to symptoms that last less than 24 hours (Hatano 1976). A stroke occurs when blood flow to part of the brain is interrupted, causing damage to the brain tissue. The two main types of stroke are ischaemic and haemorrhagic: ischaemic stroke is caused by blood clots blocking arteries in the neck or brain and accounts for 80% of stroke cases; haemorrhagic stroke results from arterial bleeding into (intracerebral) or around (subarachnoid) the brain and accounts for 20% of stroke cases (Feigin et al 2003). The degree and type of disability that follows a stroke depends on which artery is affected and which areas of the brain are damaged. Patients may experience: paralysis or problems controlling movement (particularly on one side of the body); sensory disturbances, including pain; problems using or understanding language; swallowing or visual problems; incontinence; loss of balance or co-ordination; problems with thinking, memory and reasoning; cognitive and emotional disturbances; and loss of consciousness

Dysphagia, nutrition and hydration post stroke.

In this article the author discusses the risk of dysphagia, which is a swallowing disorder, and nutrition and hydration management in stroke patients. She cites clinical guideline regarding dysphagia diagnosis and nutrition management by the Scottish Intercollegiate Guidelines Network (SIGN) of 2010 and the Intercollegiate Stroke Working Party (ISWP) of 2012, the prevalence of dysphagia among stroke patients, and enteral feeding via nasogastric tube (NGT)